[Bugfix][CPU] Fix cpu all-reduce using native pytorch implementation

[Isotr0py]

• Different from ipex.distributed, all_reduce implementation from torch.distributed won't return all-reduced tensor:
  https://github.com/pytorch/pytorch/blob/0b0da81021e061c021e515bc35d7dc0dbbb05941/torch/distributed/distributed_c10d.py#L2753-L2755

[github-actions]

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[youkaichao]

thanks for the fix!

[DarkLight1337]

Unblocked CPU tests, we can merge if it passes

[DarkLight1337]

@khluu I think we need to update CPU CI with AWS creds as well?

[DarkLight1337]

Meanwhile let's just merge this